Blind spot modules
 

My blind spot stopped working - I bought a 'used' pair on ebay - from an A5 - now when there is a car on the drivers side - the passenger side mirror glows - and vice versa. I know some cars the master and slave are swapped sides - but I thought I saw the A5 was the same as the Q5... I guess maybe I'm wrong?

For a B8 Q5, that's 8T0907566_ (master) on the left and 8T0907568_ (slave) on the right, according to the parts catalog. The Q5 is inverted compared to the A4/A5, based on this. No idea why they would change it since they are all B8 vehicles and using the same radar units.